(a) Field of the Invention
The present invention is related to a swinging linkage device disposed between a stepper and an upright bar of a stepping exerciser, more particularly to an exerciser that, by means of a linkage device that drives the upright bar and a handle to swing and turn, allows the user to twist his/her upper trunk while performing stepping exercise.
(b) Description of the Prior Art
Some existing steppers additionally provide a swinging function to allow users to swing their lower trunk while performing stepping exercise. However, as the upright bar and the handle of the stepper are fixed, users can hardly exercise their arms and upper trunk. Prior patents have taught exercisers that allow exercising of the arms by providing two handlebars that can swing back and forth. Exercisers of this type allow users to swing their arms back and forth as if running while performing stepping exercise, but they do not permit twisting of the upper trunk.
With reference to FIG. 1, U.S. Pat. No. 5,749,809 teaches a "Stepping and Swinging Exerciser" which includes a tube 14' and a handle 16' that can swing simultaneously. When the user steps on a foot pedal 21', a cable or chain 26' drives a pulley 25' at one end of a rod 23' to rotate. The other end of the rod 23' is connected to a bevel gear 24', which drives a bevel gear 17' and a pivot shaft 12' to rotate, thereby enabling the tube 14', which is secured to the pivot shaft 12', to swing therewith.
As the exerciser taught in said U.S. Pat. No. 5,749,809 employs indirect power transmission, the structure thereof is relatively complicated. Besides, the swinging action of the handle 16' can only allow the user to twist his/her waist and does not allow the user to swing his/her arms back and forth. Improvement thereon is therefore desirable.